public function createChildControls()
{
$this->_flag = new THiddenField();
$this->_flag->setID('Flag');
$this->getControls()->add($this->_flag);
$this->_busy = new TImage();
$this->_busy->setID('Busy');
$this->_busy->setImageUrl($this->getAssetUrl('ActiveFileUploadIndicator.gif'));
$this->_busy->setStyle("display:none");
$this->getControls()->add($this->_busy);
$this->_success = new TImage();
$this->_success->setID('Success');
$this->_success->setImageUrl($this->getAssetUrl('ActiveFileUploadComplete.png'));
$this->_success->setStyle("display:none");
$this->getControls()->add($this->_success);
$this->_error = new TImage();
$this->_error->setID('Error');
$this->_error->setImageUrl($this->getAssetUrl('ActiveFileUploadError.png'));
$this->_error->setStyle("display:none");
$this->getControls()->add($this->_error);
$this->_target = new TInlineFrame();
$this->_target->setID('Target');
$this->_target->setFrameUrl($this->getAssetUrl('ActiveFileUploadBlank.html'));
$this->_target->setStyle("width:0px; height:0px;");
$this->_target->setShowBorder(false);
$this->getControls()->add($this->_target);
}